It is customary in the stamping die field to have holes formed through each side of a die structure, e.g., four or more, adapted to having so-called, flat nose keeper pin assemblies slip fitted therethrough, with flat-nosed ends extending into the die cavity. The ends serve, during production cycles, as stops for a downwardly travelling die pad which holds the part to be formed. Heretofor, such keeper pin assemblies, formed close to their finished shape, were blued with a known shop use bluing paint, inserted through the holes formed in the sides of the die, the pad then lowered thereagainst, the pins removed and hand ground to eliminate high spots. This process was repeated until all four or more keeper pin assembly end extensions were as flat and as equally planar as possible, after which production cycles could begin. As such, the process was extremely time consuming and, hence, very costly for labor and lost production time.